I also use dnscache / tinydns and do not have problems with the -h
switch. Everything still runs smoothly.
Martin
PS: This is another thing we should probably be adding to the toaster
set-up instructions, at least as a note. What do you think, Bill?
Martin
Am 30.12.2008 um 19:21 schrieb Shane Chrisp:
Jeff Koch wrote:
A good pick up by Tren, I didn't think about tcpserver initially. As
far as I know, the only reason you will experience any sort of delay
is if the dns that the accepting server is not functioning properly.
I have taken to running a copy of dnscache on each of the front end
servers for qmail to use only as it is very lightweight and
extremely fast and simple to setup.
That being said, before moving to this setup I did have a problem on
a server which was having lots of trouble due to lookups failing and
it was giving 4xx temporary errors due to load and timing out
connections. Since moving to the above setup I have not seen a
repeat of these problems. Others may have different experiences that
I would be interested in hearing about as well.
Shane
#!/bin/sh
QMAILDUID=`id -u vpopmail`
NOFILESGID=`id -g vpopmail`
MAXSMTPD=`cat /var/qmail/control/concurrencyincoming`
exec /usr/local/bin/softlimit -m 8000000 \
/usr/local/bin/tcpserver -v -H -R -l 0 \
-x /home/vpopmail/etc/tcp.smtp.cdb -c "$MAXSMTPD" \
-u "$QMAILDUID" -g "$NOFILESGID" 0 smtp rblsmtpd \
-r xxxxx \
-r xxxxx \
/var/qmail/bin/qmail-smtpd \
/home/vpopmail/bin/vchkpw /bin/true 2>&1
Thanks for the clue. I see we're using the 'H' option which
prevents reverse DNS lookups. This configuration setup (with the
exception of our rblsmtpd entries) is a stock Shupp Toaster - so I
guess the question is why the stock toaster is configured not to do
reverse DNS lookups when doing so triggers the spamassassin
'RDNS_NONE' flag.
Any comments? Would rDNS lookups totally slow down a production
server?
At 02:09 AM 12/30/2008, you wrote:
What switches are you using to call tcpserver with for your qmail-
smtpd process?
t
----- Original Message -----
From: Jeff Koch <jeffk...@intersessions.com>
To: toaster@shupp.org <toaster@shupp.org>
Sent: Mon Dec 29 23:05:30 2008
Subject: Re: [toaster] Why - Received: from unknown
The receiving mailserver can do reverse DNS perfectly - just
doesn't seem
to want to do it during qmail smtp connections. I checked the
/etc/nsswitch.conf file and changed it from:
hosts: files mdns4_minimal [NOTFOUND=return] dns
to:
hosts: dns files
That didn't seem to help either. Do you think a reboot or a
service restart
is necessary after making this change?
At 11:49 PM 12/29/2008, you wrote:
>Jeff Koch wrote:
>>Hi:
>>Does anyone happen to know why all emails received by qmail are
reported
>>as 'Received: from unknown' even though the sending mailserver
clearly
>>identifies itself and has reverve DNS setup?
>>Here's a good example from an email I just recieved:
>>Received: from unknown (HELO lists.sourceforge.net)
(216.34.181.88)
>
>That suggests the reverse dns lookups are failing on that server.
Have you
>tried some lookups manually to see if they are working? I had an
issue
>similar to this just recently with a new server and it took a
while to
>realise that I had made a mistake in the nssswitch.conf file and
it was
>trying to resolve everything via ldap instead of via dns.
>
>Shane
Best Regards,
Jeff Koch, Intersessions
Best Regards,
Jeff Koch, Intersessions
